Mohammad Hossein Taleb Ali Talebali.mht@gmail.com 9/ 22/ 2019 Department of Chemical Engineering Isfahan University Of Technology, Isfahan 84156-83111, Iran Degree: M.Sc Language: Farsi Arjomand Mehrabani, Arjomand@cc.iut.ac.ir Alireza Khaz apos; Ali, arkhazali@cc.iut.ac.ir At this work, the binodal curve of [bmim][mSO 4 ] + Salt + Water systems using K 2 CO 3 , Na 2 CO 3 , Na 2 SO 4 and K 3 PO 4 .3H 2 O as the salt is investigated at 300.15, 310.15 and 320.15 K by cloud point method. The effect of salt and temperature on the ability of two – phase aqueous systems was also studied. Liquid – liquid equilibrium data, binodal curve and Tie – lines were obtained for all the two – phase systems mentioned at the above temperatures and atmospheric pressure. The length and slope of Tie – lines for all systems were calculated and the influence of temperature on these data was studied. The results showed that the salt cation type had the most effect on the formation of aqueous two – phase system while the effect of temperature on the two – phase curve of the investigated systems was negligible. Among the salts used, K 3 PO 4 is more potent than other salts. As the temperature increases, the binodal curves farther away from the coordinate axes, reducing the two – phase region. Therefore, it is possible to create aqueous two – phases system at lower temperature with lower concentration of ionic liquid and salt. The result is that lower temperatures are more suitable for creating aqueous two – phase system in the studied systems. As the temperature increases, the absolute magnitude of the slope of the Tie – lines decreases slowly. Key Words : Aqueous Two Phase System, Ionic liquid, Tie – Line, Binodal curve, Salt